Text preview for : 14n21ns.pdf part of TOSHIBA 14n21ns TOSHIBA TV 14n21ns.pdf



Back to : 14n21ns.pdf | Home

TOSHIBA


SERVICE MANUAL

COLOUR TELEVISION
14N21NS




PRINTED IN UK. 2002 C
SERVICING NOTICES ON CHECKING
1. KEEP THE NOTICES 6. AVOID AN X-RAY
As for the places which need special attentions, Safety is secured against an X-ray by consider-
they are indicated with the labels or seals on the ing about the cathode-ray tube and the high
cabinet, chassis and parts. Make sure to keep the voltage peripheral circuit, etc.
indications and notices in the operation manual. Therefore, when repairing the high voltage pe-
ripheral circuit, use the designated parts and
2. AVOID AN ELECTRIC SHOCK make sure not modify the circuit.
There is a high voltage part inside. Avoid an Repairing except indicates causes rising of high
electric shock while the electric current is voltage, and it emits an X-ray from the cathode-
flowing. ray tube.
3. USE THE DESIGNATED PARTS 7. PERFORM A SAFETY CHECK AFTER
The parts in this equipment have the specific SERVICING
characters of incombustibility and withstand
Confirm that the screws, parts and wiring which
voltage for safety. Therefore, the part which is
were removed in order to service are put in the
replaced should be used the part which has
original positions, or whether there are the
the same character.
portions which are deteriorated around the
Especially as to the important parts for safety
serviced places serviced or not. Check the
which is indicated in the circuit diagram or the
insulation between the antenna terminal or
table of parts as a mark, the designated
external metal and the AC cord plug blades.
parts must be used.
And be sure the safety of that.
4. PUT PARTS AND WIRES IN THE (INSULATION CHECK PROCEDURE)
ORIGINAL POSITION AFTER
1. Unplug the plug from the AC outlet.
ASSEMBLING OR WIRING 2. Remove the antenna terminal on TV and turn
There are parts which use the insulation on the TV.
material such as a tube or tape for safety, or 3. Insulation resistance between the cord plug
which are assembled in the condition that terminals and the eternal exposure metal
these do not contact with the printed board. [Note 2] should be more than 1M ohm by
The inside wiring is designed not to get closer using the 500V insulation resistance meter
to the pyrogenic parts and high voltage parts. [Note 1].
Therefore, put these parts in the original 4. If the insulation resistance is less than 1M
positions. ohm, the inspection repair should be
required.
5. TAKE CARE TO DEAL WITH THE
[Note 1]
CATHODE-RAY TUBE
If you have not the 500V insulation
In the condition that an explosion-proof cathode-
resistance meter, use a Tester.
ray tube is set in this equipment, safety is
secured against implosion. However, when [Note 2]
removing it or serving from backward, it is External exposure metal: Antenna terminal
dangerous to give a shock. Take enough care to Earphone jack
deal with it.


HOW TO ORDER PARTS
Please include the following informations when you order parts. (Particularly the VERSION LETTER.)
1. MODEL NUMBER and VERSION LETTER
The MODEL NUMBER can be found on the back of each product and the VERSION LETTER can be
found at the end of the SERIAL NUMBER.
2. PART NO. and DESCRIPTION
You can find it in your SERVICE MANUAL.


IMPORTANT
Inferior silicon grease can damage IC's and transistors.
When replacing an IC's or transistors, use only specified silicon grease (YG6260M).
Remove all old silicon before applying new silicon.




A1-1
CONTENTS


SERVICING NOTICES ON CHECKING ...................................................................................................... A1-1
HOW TO ORDER PARTS ........................................................................................................................... A1-1
IMPORTANT ................................................................................................................................................ A1-1
CONTENTS ................................................................................................................................................. A2-1
GENERAL SPECIFICATIONS .................................................................................................................... A3-1~A3-5
DISASSEMBLY INSTRUCTIONS
1.REMOVAL OF ANODE CAP .............................................................................................................. B1-1
2.REMOVAL AND INSTALLATION OF FLAT PACKAGE IC ............................................................... B2-1, B2-2
SERVICE MODE LIST ................................................................................................................................. C-1
CONFIRMATION OF HOURS USED .......................................................................................................... C-1
WHEN REPLACING EEPROM( MEMORY) IC ........................................................................................... C-2
ELECTRICAL ADJUSTMENTS .................................................................................................................. D-1~D-5
BLOCK DIAGRAM ...................................................................................................................................... E-1, E-2
PRINTED CIRCUIT BOARDS
MAIN/CRT ............................................................................................................................................... F-1~F-4
SCHEMATIC DIAGRAMS
MICON/TUNER ....................................................................................................................................... G-1, G-2
CHROMA/SIF/VIF/21PIN ........................................................................................................................ G-3, G-4
POWER .................................................................................................................................................. G-5, G-6
DEFLECTION/CRT ................................................................................................................................. G-7, G-8
SOUND AMP .......................................................................................................................................... G-9, G-10
WAVEFORMS ............................................................................................................................................. H-1, H-2
MECHANICAL EXPLODED VIEW .............................................................................................................. I-1
MECHANICAL REPLACEMENT PARTS LIST .......................................................................................... J1-1
ELECTRICAL REPLACEMENT PARTS LIST ............................................................................................ J2-1~ J2-4




A2-1
GENERAL SPECIFICATIONS
G-1 TV CRT CRT Size / Visual Size 14 inch / 335.4mmV
System CRT Type Normal
Deflection 90 degree
Magnetic Field BV/BH +0.45G/0.18G
Color System PAL
Speaker 1 Speaker
Position Bottom
Size 1.5 x3.0 Inch
Impedance 8 ohm
Sound Output MAX 1.0 W
10%(Typical) 0.8 W
DDR SECAM No
NTSC3.58(AV)+NTSC4.43 Yes
PAL60Hz Yes
G-2 Tuning Broadcasting System CCIR System B/G
System Tuner and System 1Tuner
Receive CH Destination Ohers
Tuning System F-Synth
Input Impedance VHF/UHF 75 ohm
E2 - E4, X - Z+2, S1 - S10, E5 - E12,
CH Coverage S11 - S41, E21 - E69
Intermediate B/G
Frequency Picture(FP) 38.9 MHz
Sound(FS) 33.4 MHz
FP-FS 5.5 MHz
Preset CH 100
Stereo/Dual TV Sound No
Tuner Sound Muting Yes
G-3 Power Power Source AC 230V-240V AC 50Hz
DC
Power Consumption at AC
44 W at AC 230 V 50 Hz
Stand by (at AC) 3 W at AC 230 V 50 Hz
Per Year -- kWh/Year
Protector Power Fuse Yes
G-4 Regulation Safety CE(EN60065:98)
Radiation CE
X-Radiation -
G-5 Temperature Operation +5oC ~ +40oC
Storage -20oC ~ +60oC
G-6 Operating Humidity Less then 80% RH




A3-1
GENERAL SPECIFICATIONS
G-7 On Screen Menu Yes
Display Menu Type Character
Picture Yes
Contrast Yes
Brightness Yes
Colour Yes
Tint (NTSC Only) Yes
Sharpness Yes
Audio No
Bass No
Treble No
Balance No
BBE On/Off No
Stable Sound On/Off No
CH Tuning Yes
Matual Yes
Auto Yes
CH Allocation Yes
Language Yes
Clock Set No
On/OffTimer Set Yes
On Timer Set No
Pin Code Registration No
Panel Lock Yes
Nicam Auto Off No
AV Colour System Yes
Sound System No
Auto 4:3 Default No
AV2 Output No
Output Source No
Source No
Control Level Yes
Volume Yes
Brightness Yes
Contrast Yes
Colour Yes
Tint (NTSC Only) Yes
Sharpness Yes
Tuning Yes
Bass No
Treble No
Balance No
Back Light No
Nicam ST No
Tone 1/2 (A/B) No
Surround On/Off No
Pin Code No
AV Yes
Skip No
Channel Yes
Hotel Lock No
Sleep Timer No
Wide Mode No
Sound Mute Yes
G-8 OSD Language English French Spanish
Germany Italian
Polski Turkey Sweden
Netherland Portgal
Norway Finland Denmark
Czech Slovak Hungarian
Russian Greek
G-9 Clock and Sleep Timer Max Time - Min
Timer Step - Min
Clock No
On Timer Program( On Tim) Yes
Off Timer Program( 0ff Tim) Yes
Wake Up Timer No
Timer Back-up (at Power Off Mode) more than -- Min Sec




A3-2
GENERAL SPECIFICATIONS
G-10 Remote Unit RK-EY (CT-835)
Control Glow in Dark Remocon No
Format NEC
Custom Code 40-BF h
Power Source Voltage(D.C) 3V
UM size x pcs UM-4 x 2 pcs
Total Keys 32 Keys
Keys Power Yes
1 Yes
2 Yes
3 Yes
4 Yes
5 Yes
6 Yes
7 Yes
8 Yes
9 Yes
0 Yes
Volume Up / + Yes
Volume Down / - Yes
Previous Yes
Select Picture Yes
Menu Yes
OK(Enter) Yes
EXIT No
Audio Select No
Sleep Timer No
Mute Yes
T'TEXT Keys TEXT / MIX / TV Yes
CH Up / Page Up Yes
CH Down / Page Down Yes
Red Yes
Green Yes
Yellow Yes
Cyan Yes
TEXT F/T/B Yes
Reveal Yes
TIMED PAGE(SUB PAGE) Yes
CALL / TEXT INDEX Yes
INPUT SELECT Yes
TEXT HOLD Yes
TIME / TXCL Yes
G-11 Features Auto Degauss Yes
Auto Shut Off Yes
Canal+ No
CATV No
Anti-theft(Back Up 30 Min.) No
Memory(Last CH) Yes
Memory(Last Volume) Yes
BBE No
Auto Search Yes
CH Allocation Yes
Just Clock Function No
Game Position No
CH Label No
VM Circuit No
Full OSD No
Unitext No
Fastext Yes
Top Text No
Premiere No
Comb Filter No
Lines
Auto CH Memory No
Stable Sound No
Auto Set Up No
FBT Leak Test Protect Yes
Power ON Memory Yes
Previous (Quick View) Yes
Panel Lock Yes
Double Focus & Dynamic Focus No
Wss Signal Wide Change No
Virtual Dolby Surround No
Hotel Lock No




A3-3
GENERAL SPECIFICATIONS
G-12 Accessories Owner's Manual Language Swedish, Norwegian, Danish,
Finnish, Turkish
w/Guarantee Card No
Remote Control Unit Yes
Rod Antenna Yes
Poles 2Pole
Terminal D-type
Loop Antenna No
Terminal -
U/V Mixer No
DC Car Cord (Center+) No
Guarantee Card No
Warning Sheet No
Circuit Diagram No
Antenna Change Plug No
Service Facility List No
Important Safeguard Yes (Owner's Manual In)
Dew/AHC Caution Sheet No
AC Plug Adapter No
Quick Set-up Sheet Yes
Battery Yes
UM size x pcs UM-4 x 2 pcs
OEM Brand No
AC Cord No
AV Cord (2Pin-1Pin) No
Registration Card No
PTB Sheet No
300 ohm to 75 ohm Antenna Adapter No
G-13 Interface Switch Front Power (Tact Sw) No
System Select No
Main Power SW Yes
Sub Power No
Channel Up Yes
Channel Down Yes
Volume Up Yes
Volume Down Yes
Rear AC/DC No
TV/CATV Selector No
Degauss No
Main Power SW No
Indicator Power No
Stand-by No
Stand-by/ON , On Timer Yes(Red , Green)
Stand-by/ON No
On Timer No
Terminals Front Video Input Yes
Audio Input Yes
Other Terminal EAR Phone
Rear Video Input(Rear1) No
Video Input(Rear2) No
Audio Input(Rear1) No
Audio Input(Rear2) No
Video Output No
Audio Output No
Euro Scart(21Pin) No
S-INPUT
Euro Scart(21Pin) Yes ( x1 )
RGB-INPUT Yes ( x1 )
Component Input No
Diversity No
Ext Speaker No
DC Jack 12V(Center +) No
VHF/UHF Antenna Input D Type
AC Outlet No
G-14 Set Size Approx. W x D x H (mm) 362 x 360 x 373
G-15 Weight Net (Approx.) 9.5 kg ( --- lbs)
Gross (Approx.) 11.5kg ( ---lbs)




A3-4
GENERAL SPECIFICATIONS
G-16 Carton Master Carton No
Content ---- Sets
Material -- /--
Dimensions W x D x H(mm) -- x -- x --
Description of Origin Yes
Gift Box Yes
Material Double/Brown
Dimensions W x D x H(mm) 440 x 408 x 380
Design As per Buyer's
Description of Origin Yes
Drop Test Natural Dropping At 1 Corner / 3
Edges / 6 Surfaces
Height (cm) 62
Container Stuffing 866 Sets/40' container




A3-5
DISASSEMBLY INSTRUCTIONS
1. REMOVAL OF ANODE CAP 3. After one side is removed, pull in the opposite direction to
remove the other.
Read the following NOTED items before starting work.
NOTE
* After turning the power off there might still be a potential
voltage that is very dangerous. When removing the Take care not to damage the Rubber Cap.
Anode Cap, make sure to discharge the Anode Cap's INSTALLATION
potential voltage.
1. Clean the spot where the cap was located with a small
* Do not use pliers to loosen or tighten the Anode Cap
amount of alcohol. (Refer to Fig. 1-3.)
terminal, this may cause the spring to be damaged.
REMOVAL
1. Follow the steps as follows to discharge the Anode Cap. Location of Anode Cap
(Refer to Fig. 1-1.)
Connect one end of an Alligator Clip to the metal part of a
flat-blade screwdriver and the other end to ground.
While holding the plastic part of the insulated Screwdriver,
touch the support of the Anode with the tip of the
Screwdriver.
A cracking noise will be heard as the voltage is discharged.



GND on the CRT
Fig. 1-3

NOTE
Confirm that there is no dirt, dust, etc. at the spot where
the cap was located.
2. Arrange the wire of the Anode Cap and make sure the
wire is not twisted.
3. Turn over the Rubber Cap. (Refer to Fig. 1-4.)




Screwdriver CRT
Support
Alligator Clip

GND on the CRT
Fig. 1-1

2. Flip up the sides of the Rubber Cap in the direction of the Fig. 1-4
arrow and remove one side of the support.
(Refer to Fig. 1-2.) 4. Insert one end of the Anode Support into the anode button,
then the other as shown in Fig. 1-5.
Rubber Cap




CRT
Support Support
Fig. 1-2
CRT
Fig. 1-5

5. Confirm that the Support is securely connected.
6. Put on the Rubber Cap without moving any parts.


B1-1
DISASSEMBLY INSTRUCTIONS
2. REMOVAL AND INSTALLATION OF 3. When IC starts moving back and forth easily after
desoldering completely, pickup the corner of the IC using
FLAT PACKAGE IC a tweezers and remove the IC by moving with the IC
desoldering machine. (Refer to Fig. 2-3.)
REMOVAL
NOTE
1. Put the Masking Tape (cotton tape) around the Flat
Some ICs on the PCB are affixed with glue, so be
Package IC to protect other parts from any damage. careful not to break or damage the foil of each IC
(Refer to Fig. 2-1.) leads or solder lands under the IC when removing it.
NOTE
Masking is carried out on all the parts located within Blower type IC
10 mm distance from IC leads. desoldering
machine


Masking Tape IC
(Cotton Tape)




Tweezers




Fig. 2-1
IC
Fig. 2-3
2. Heat the IC leads using a blower type IC desoldering
machine. (Refer to Fig. 2-2.)
4. Peel off the Masking Tape.
NOTE
Do not add the rotating and the back and forth 5. Absorb the solder left on the pattern using the Braided
directions force on the IC, until IC can move back and Shield Wire. (Refer to Fig. 2-4.)
forth easily after desoldering the IC leads completely. NOTE
Do not move the Braided Shield Wire in the vertical
direction towards the IC pattern.
Blower type IC
desoldering machine




Braided Shield Wire


Soldering Iron




IC
IC pattern Fig. 2-4
Fig. 2-2




B2-1
DISASSEMBLY INSTRUCTIONS
INSTALLATION 4. When bridge-soldering between terminals and/or the
soldering amount are not enough, resolder using a Thin-
1. Take care of the polarity of new IC and then install the tip Soldering Iron. (Refer to Fig. 2-8.)
new IC fitting on the printed circuit pattern. Then solder
each lead on the diagonal positions of IC temporarily.
(Refer to Fig. 2-5.)
Thin-tip Soldering Iron IC




Soldering Iron




Fig. 2-8

5. Finally, confirm the soldering status on four sides of the
Solder temporarily Solder temporarily
IC using a magnifying glass.
Confirm that no abnormality is found on the soldering
Fig. 2-5 position and installation position of the parts around the
IC. If some abnormality is found, correct by resoldering.
2. Supply the solder from the upper position of IC leads NOTE
sliding to the lower position of the IC leads.
When the IC leads are bent during soldering and/or
(Refer to Fig. 2-6.)
repairing, do not repair the bending of leads. If the
bending of leads are repaired, the pattern may be
damaged. So, be always sure to replace the IC in this
case.



Solder Soldering Iron




IC Supply soldering
from upper position
to lower position




Fig. 2-6

3. Absorb the solder left on the lead using the Braided
Shield Wire. (Refer to Fig. 2-7.)
NOTE
Do not absorb the solder to excess.


Soldering Iron
IC




Braided Shield Wire



Fig. 2-7




B2-2
SERVICE MODE LIST
This unit provided with the following SERVICE MODES so you can repair, examine and adjust easily.
To enter the Service Mode, press both set key and remote control key for more than 2 seconds.

Set Key Remocon Key Operations
Reset the user setting items (PICTURE, VOLUME and LANGUAGE) to the initial state
VOL. (-) MIN 0
for delivery.

Initialization of the factory.
NOTE: Do not use this for the normal servicing.
VOL. (-) MIN 1
If you set a factory initialization, the memories are reset such as the
channel setting, and the POWER ON total hours.

POWER ON total hours is displayed on the screen.
Refer to the "CONFIRMATION OF HOURS USED".
VOL. (-) MIN 6
Can be checked of the INITIAL DATA of MEMORY IC.
Refer to the "WHEN REPLACING EEPROM (MEMORY) IC".

Writing of EEPROM initial data.
VOL. (-) MIN 8
NOTE: Do not use this for the normal servicing.

Display of the Adjustment MENU on the screen.
VOL. (-) MIN 9
Refer to the "ELECTRICAL ADJUSTMENT" (On-Screen Display Adjustment).




CONFIRMATION OF HOURS USED
POWER ON total hours can be checked on the screen. Total hours are displayed in 16 system of notation.
NOTE: If you set a factory initialization, the total hours is reset to "0".
1. Set the VOLUME to minimum. ADDRESS DATA

2. Press both VOL. DOWN button on the set and Channel
button (6) on the remote control for more than 2 seconds.
3. After the confirmation of using hours, turn off the power. INIT 01 00 Initial setting content of MEMORY IC.
CRT ON 0010 POWER ON total hours.
= (16 x 16 x 16 x thousands digit value)
+ (16 x 16 x hundreds digit value)
+ (16 x tens digit value)
FIG. 1 + (ones digit value)




C-1
WHEN REPLACING EEPROM (MEMORY) IC
If a service repair is undertaken where it has been required to change the MEMORY IC, the following steps should be taken to
ensure correct data settings while making reference to TABLE 1.
Note: No need setting for the position of the mark @ due to the adjustment value.

INI +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +A +B +C +D +E +F
00 --- 00 00 00 00 41 80 48 00 23 27 01 03 30 06 14

10 10 00 80 80 80 3C 40 @ @ 9F @ 80 00 44 @ @

20 @ @ @ @ C0 00 @ 20 @ 00 18 @ 00 @ @ 0F

30 00 @ @ @ 07 00 00 00 00 00 00 00 00 00 00 00

40 7F 6F 5F 4F 3F 39 34 2F 2D 2B 29 27 25 23 21 20

50 1F 1E 1D 1C 1B 1A 19 18 17 16 15 14 13 13 12 12

60 11 11 10 10 0F 0F 0E 0E 0D 0D 0C 0C 0B 0B 0A 0A

70 09 09 08 08 07 07 06 05 04 04 03 03 03 02 02 02

80 22 23 CD CF D2 D6 D9 96 98 9C 9D 55 56 58 5A 5C

90 5D 5E --- --- --- --- --- --- --- --- --- --- --- --- --- ---

Table 1
1. Enter DATA SET mode by setting VOLUME to minimum.
2. Press both VOL. DOWN button on the set and Channel button (6) on the remote control for more than 2 seconds.
ADDRESS and DATA should appear as FIG 1.

ADDRESS DATA




INIT 01 00
CRT ON 0010



Fig. 1
3. ADDRESS is now selected and should "blink". Using the VOL. +/- button on the remote, step through the ADDRESS until
required ADDRESS to be changed is reached.
4. Press OK to select DATA. When DATA is selected, it will "blink".
5. Again, step through the DATA using VOL. +/- button until required DATA value has been selected.
6. Pressing OK will take you back to ADDRESS for further selection if necessary.
7. Repeat steps 3 to 6 until all data has been checked.
8. When satisfied correct DATA has been entered, turn POWER off (return to STANDBY MODE) to finish DATA input.
The unit will now have the correct DATA for the new MEMORY IC.




C-2
ELECTRICAL ADJUSTMENTS
1. ADJUSTMENT PROCEDURE 2. BASIC ADJUSTMENTS
Read and perform these adjustments when repairing the 2-1: CONSTANT VOLTAGE
circuits or replacing electrical parts or PCB assemblies. Place the set with Aging Test for more than 5 minutes.
1.
CAUTION 2. Connect the digital voltmeter to TP501.
3. Set condition is AV MODE without signal.